Web Testing for Reliability Improvement - Advances in Computers - page 205

T ABLE III
T OP E NTRY P AGES TO SMU/SEAS

Entry page Occurrences

/index.html 18 , 646

/ce/index.html 2778

/co/cams/index.html 2568

/ce/smu/index.html 2327

/netech/index.html 2139

/disted/phd/index.html 1036

/co/cams/clemscam.html 963

/disted/index.html 878

/cse/index.html 813

no such exit page report is produced by any existing analyzer. This problem can be
handled implicitly by specific usage sequences associated with specific test cases:
The end of a usage sequence is the exit point from the UMM. This decision implies
that frequently visited pages are also more likely to be the exit node than infrequently
visited pages, which makes logical sense.
Figure 8 shows the top-level Markov chain of the UMM for the SMU/SEAS web
site. The following information is captured and presented:

Each node is labeled by its associated web file or directory name, and the total
outgoing direct hits calculated. For example, out = 2099 for the root node
“ /index.html ,” indicates that the total direct hits from this node to its chil-
dren pages is 2099.
Each link is labeled with its direct hit count, instead of branching probability,
to make it easier to add missing branching information should such information
become available later. However, relative frequencies and conditional branching
probabilities for links originating from a given node can be deduced easily.
For example, the direct hit count from the page “ /index.html ” to the page
“ gradinfo.html ” is 314; and the conditional branching probability for this
link is 314 / 2099 = 20 . 5%.
Infrequent direct hits to other pages are omitted from the model to simplify the
model and highlight frequently followed sequences. However, the omitted direct
hits can be calculated by subtracting out direct hits represented in the diagram
from the total “ out ” hits of the originating node. For example, there are direct
hits to nine other pages from the root page “ /index.html .” The combined
direct hits are: 2099 − 431 − 314 − 240 − 221 = 893.